In a shelter made of plastic sheets and bamboo next to a reeking stream in the world's largest refugee settlement, Rohingya Nazma Akter recalled how her daughter was trafficked seven months ago.

Rashida, 17, was picked up next to a health clinic in a camp in southeast Bangladesh by a man who had been courting her by phone for sometime while her mother visited the doctor.

The man, however, turned out to be a trafficker.

Two days later Rashida was rescued by the police at Jashore, a regional hub for sex trafficking about 500 km (310 miles) north of the camps near to Bangladesh's border with India.

It has been 18 months since more than 730,000 mainly Muslim Rohingya fled persecution in Buddhist-dominated Myanmar and set up camps across the border in a coastal district about 40 km (25 miles) south of Cox's Bazar, Bangladesh's top tourist location.

The camps, sprawled over about 6,000 acres — just under half the size of Manhattan — have become more organized, but recent police activity suggested the risk of being trafficked has increased due to the promise of work and better lives.

For there are no signs the Rohingya will be able to leave the camps any time soon. Plans for repatriation were put on hold by the Bangladesh government last November amid protests in the camp with a vow no one will be sent back against their will.

"In the middle there were talks about repatriation. Once that slowed down, we noticed an increase in trafficking," said Major Mehedi Hasan, company commander of Bangladesh's elite police force Rapid Action Batallion (RAB).

Latest police records showed that on Jan. 30, police at Jashore rescued five Rohingya girls and one boy, all teenagers, from being trafficked into India.

Six days earlier RAB officers rescued 11 Rohingya Muslims from Chittagong, a major coastal city and financial center in southeast Bangladesh about 170 km from the camps.

Last November, law enforcement agencies rescued 57 Rohingya refugees from Malaysia-bound boats on three different occasions.

Anti-trafficking groups fear the human trafficking routes to southeast Asia through the Bay of Bengal, which became active around 2010, are now being used to smuggle increasingly desperate Rohingya refugees out of Bangladesh.

Lacking data

The Bangladesh government has not released an official figure of the number of Rohingya who have been trafficked but aid agencies have come up with various numbers which highlight the severity of the issue.

Jishu Barua, programme coordinator for Young Power in Social Action, a non-profit group that deals with trafficking, said an analysis of local papers suggested at least 200 Rohingya had been rescued here in the last three months.

"The numbers have increased. We are telling everyone in the camps to be more careful. We are spreading awareness through different events, such as street dramas and courtyard briefings," Barua told the Thomson Reuters Foundation.

The United Nations' International Organization for Migration (IOM) has identified about 204 cases of trafficking so far.

"But this is just a fraction of what we believe is happening," said IOM spokeswoman Fiona MacGregor, adding that young girls were particularly vulnerable to being taken as domestic workers both locally and within Bangladesh. "There are cases where people don't know what is going on and then others that do take the risk because they feel there is no other choice."

The government view is that improving people's livelihood at the camps was the only way to curb human trafficking from the area that was known to be at the heart of a people smuggling business long before the Rohingya influx.

Bangladesh bars the Rohingya from leaving the camps, or holding jobs other than participating in small-scale cash-for-work programs run by humanitarian agencies.

In the past, traffickers misled hundreds of people who wanted to go to Malaysia and trapped them in camps in the border areas of Thailand and Malaysia, torturing them until their families agreed to pay up to $1,800, a fortune for impoverished migrants.

This came to light in 2015 with the discovery of scores of mass graves believed to contain the bodies of Rohingya and Bangladeshi migrants.

"Trafficking was present in the past and it is present today as well," said Shamimul Huq Pavel, a government officer with the Refugee, Relief and Repatriation Commission (RRRC), a government organization created to deal with the Rohingya crisis. "We are trying to improve the situation in the camps here. Once that happens, the situation will improve."

With trafficking on the rise, Bangladesh law enforcers have also stepped up activities to crack down on trafficking, as has Malaysia, which announced last month it would set up an official inquiry to investigate human trafficking camps in border areas.

"We have increased our surveillance near the boat areas," said RAB's Hasan.

Reintegration troubles

While Akter was relieved to get her daughter back, she knew she would have to keep her story quiet. The names of both were changed in this story to protect their identities.

"If people knew her story, no one would marry her," said Akter, stressing that the Rohingya were a conservative community in which men and women were largely segregated in Myanmar. "Yes, she was foolish and she was trapped. But we live in a problematic area. It can happen to anyone. We have heard many (stories) of children disappearing in the camps."

Since her return, Rashida has married and lives near her mother in Balukhali camp, one of 34 camps in the settlement — but her husband does not know about the trafficking.

"She is happy today. Let her be. There's no need to bring these issues up again," said Akter, who lives with her husband and two younger daughters in the camp.

While Rashida escaped public stigma on her return, 28-year-old Ramida Khatun — who also requested anonymity for her security — from the largest camp, Kutupalong, was not so lucky.

Last May, Khatun was forced by her husband to travel to Sylhet, a city 500 km from the camps, along with a trafficker to get a Bangladeshi passport so the couple could go to Malaysia.

According to Khatun's uncle, she went to Sylhet with two other Rohingya women and stayed at a hotel with the trafficker for nine days before the police rescued her.

When she returned to the camp, she faced public insults from the leader of her block for days and those memories haunt her.

"The insults have stopped. No one troubles me now. But whenever I think about those days, my head begins to hurt a lot," Khatun told the Thomson Reuters Foundation via an interpreter at the Kutupalong camp.